<script setup>
import { ref, watch } from "vue"
import { useMouseInElement } from '@vueuse/core'
// 图片列表
defineProps({
    imageList: {
        type: Array,
        default: () => { }
    }

})
// const imageList = [
//     "https://yanxuan-item.nosdn.127.net/d917c92e663c5ed0bb577c7ded73e4ec.png",
//     "https://yanxuan-item.nosdn.127.net/e801b9572f0b0c02a52952b01adab967.jpg",
//     "https://yanxuan-item.nosdn.127.net/b52c447ad472d51adbdde1a83f550ac2.jpg",
//     "https://yanxuan-item.nosdn.127.net/f93243224dc37674dfca5874fe089c60.jpg",
//     "https://yanxuan-item.nosdn.127.net/f881cfe7de9a576aaeea6ee0d1d24823.jpg"
// ]

//！小图切换，大图显示
const activeIndex = ref(0)
const enterhandler = (i) => {
    activeIndex.value = i
    console.log(mask.value.offsetWidth);
}

//!获取鼠标相对位置
const target = ref(null)
const { elementX, elementY, isOutside } = useMouseInElement(target)
//！获得mask，移动位置和大图的移动
const left = ref(0)
const top = ref(0)
const mask = ref(null)
const bX = ref(0)
const bY = ref(0)

watch([elementX, elementY, isOutside], () => {
    if (isOutside.value == false) {
        //!横向
        if (elementX.value > mask.value.offsetWidth / 2 && elementX.value < (mask.value.offsetWidth / 2) * 3) {
            left.value = elementX.value - mask.value.offsetWidth / 2
            bX.value = -2 * left.value
        }
        //！纵向
        if (elementY.value > mask.value.offsetWidth / 2 && elementY.value < (mask.value.offsetWidth / 2) * 3) {
            top.value = elementY.value - mask.value.offsetWidth / 2
            bY.value = -2 * top.value
        }
        //！边界
        if (elementX.value > (mask.value.offsetWidth / 2) * 3) {
            left.value = (mask.value.offsetWidth)
        }
        if (elementX.value < (mask.value.offsetWidth / 2)) {
            left.value = 0
        }
        if (elementY.value > (mask.value.offsetWidth / 2) * 3) {
            top.value = (mask.value.offsetWidth)
        }
        if (elementY.value < (mask.value.offsetWidth / 2)) {
            top.value = 0
        }
    }
})
</script>


<template>
    <!-- {{ elementX }}, {{ elementY }}, {{ isOutside }} -->
    <div class="goods-image">
        <!-- 左侧大图-->
        <div class="middle" ref="target">
            <img :src="imageList[activeIndex]" alt="" />
            <!-- 蒙层小滑块 -->
            <div class="layer" :style="{ left: `${left}px`, top: `${top}px` }" ref="mask" v-show="isOutside == false"></div>
        </div>
        <!-- 小图列表 -->
        <ul class="small">
            <li v-for="(img, i) in imageList" :key="i" @click="enterhandler(i)" :class="{ active: i == activeIndex }">
                <!--//！ active-class是用于路由 -->
                <img :src="img" alt="" />
            </li>
        </ul>
        <!-- 放大镜大图 -->
        <div class="large" :style="[
            {
                backgroundImage: `url(${imageList[activeIndex]})`,
                backgroundPositionX: `${bX}px`,
                backgroundPositionY: `${bY}px`,
            },
        ]" v-show="isOutside == false"></div>
    </div>
</template>

<style scoped lang="scss">
.goods-image {
    width: 480px;
    height: 400px;
    position: relative;
    display: flex;

    .middle {
        width: 400px;
        height: 400px;
        background: #f5f5f5;
    }

    .large {
        position: absolute;
        top: 0;
        left: 412px;
        width: 400px;
        height: 400px;
        z-index: 500;
        box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
        background-repeat: no-repeat;
        // 背景图:盒子的大小 = 2:1  将来控制背景图的移动来实现放大的效果查看 background-position
        background-size: 800px 800px;
        background-color: #f8f8f8;
    }

    .layer {
        width: 200px;
        height: 200px;
        background: rgba(0, 0, 0, 0.2);
        // 绝对定位 然后跟随咱们鼠标控制left和top属性就可以让滑块移动起来
        left: 0;
        top: 0;
        position: absolute;
    }

    .small {
        width: 80px;

        li {
            width: 68px;
            height: 68px;
            margin-left: 12px;
            margin-bottom: 15px;
            cursor: pointer;

            &:hover,
            &.active {
                border: 2px solid $xtxColor;
            }
        }
    }
}
</style>